1. The Field of the Invention
This invention relates to medical procedures and apparatus in general, and more particularly to bone fixation systems and related medical procedures that can be used in reconstructing a ligament.
2. The Relevant Technology
A ligament is a piece of fibrous tissue which connects one bone to another. Ligaments are frequently damaged (e.g., detached or torn or ruptured, etc.) as the result of injury and/or accident. A damaged ligament can impede proper motion of a joint and cause significant pain.
Various procedures have been developed to repair or replace a damaged ligament. The specific procedures used depend on the particular ligament which is to be restored and on the extent of the damage.
One ligament which is frequently damaged as the result of injury and/or accident is the anterior cruciate ligament (ACL). Looking now at FIG. 1, the ACL 5 extends between the top of the tibia 10 and the bottom of the femur 15. A damaged ACL can cause instability of the knee joint and cause substantial pain and arthritis.
Numerous procedures have been developed to restore the ACL through a graft ligament replacement. In general, and looking now at FIG. 2, these ACL replacement procedures involve drilling a bone tunnel 20 through tibia 10 and up into femur 15. Then a graft ligament 25, consisting of a harvested or artificial ligament or tendon(s), is passed through the tibial portion 30 of tunnel 20 (sometimes referred to as the “tibial tunnel”), across the interior of the joint, and up into the femoral portion 35 of tunnel 20 (sometimes referred to as the “femoral tunnel”). Then a distal portion of graft ligament 25 is secured in femoral tunnel 35, and a proximal portion of graft ligament 25 is secured in tibial tunnel 30.